docs: def _cleanup_buffer(self):
          '''
          Periodically cleanup the buffer.
          '''
          if not self._buffer:
              return
          while True:
              time.sleep(60)
              log.debug('Cleaning up buffer')
              items = self._buffer.items()
              # The ``items`` function should also cleanup the buffer
              log.debug('Collected items')
              log.debug(list(items))